四分律行事鈔資持記 3.94

3.94

次料揀須否中，初總標。若下，別示；前明無藍須結，初示相判定。由本不結，但隨住舍，難護易離；今若結之，遍界通護，故結有益。（《注羯磨》作界寬藍狹，與此事別義同，故知須結，則通兩相。）謂下，出不結之患。僧院即上住舍。勢分內者，一切自然衣界之外，各有十三步勢分。二下，次明餘二不須。藍界等者，尚不須結；況界小乎！借令大界出藍十三步許，結亦徒然。結竟下，示加結之過；二相俱有，院外失衣；界小於藍，院內亦失。

Next, in evaluating whether it is necessary or not, first it generally designates. From "If..." downward, it specifically shows. Earlier, it clarifies that where there is no monastery it must be demarcated, first showing the characteristics and making the determination. Because originally it was not demarcated, it merely follows the dwelling dwellings; protection is difficult and separation easy. Now if it is demarcated, it universally protects throughout the boundary; hence demarcating it has benefit. (The Annotated Karmavācanā makes the boundary wide and the monastery narrow; this is different in fact but identical in meaning, hence we know that if it must be demarcated, it applies to both characteristics.) From "Meaning..." downward, it sets forth the harms of not demarcating. The monastic compound is the aforementioned dwelling dwellings. "Within the sphere of influence": outside all natural robe-boundaries, there is in each case a sphere of influence of thirteen paces. From "Second..." downward, it next clarifies that the remaining two are not necessary. If the monastery and the boundary are equal, it is not even necessary to demarcate; how much less so if the boundary is smaller! Even granting that the great boundary extends beyond the monastery by about thirteen paces, demarcating it would also be in vain. From "After demarcation..." downward, it shows the faults of superfluous demarcation: both characteristics exist, and outside the compound robes are lost; if the boundary is smaller than the monastery, they are lost inside the compound as well.